Share-Based Compensation - Additional Information (Detail) - USD ($) |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2019 |
Sep. 30, 2018 |
Sep. 30, 2019 |
Sep. 30, 2018 |
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| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||||
| Share-based compensation expense | $ 895,000 | $ 850,000 | $ 2,300,000 | $ 2,700,000 |
| Related tax benefits on non-qualified stock options | $ 268,000 | $ 238,000 | $ 680,000 | $ 746,000 |
| Number of shares, stock options exercised (shares) | 180,000 | 0 | 181,900 | 25,750 |
| Stock option awards | ||||
| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||||
| Unrecognized share-based compensation expense | $ 0 | $ 0 | ||
| X | ||||||||||
- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of cost not yet recognized for nonvested award under share-based payment arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of tax benefit for recognition of expense of award under share-based payment arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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